Global Patent Index - EP 0881991 B1

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Title (fr)

Publication

Application

Priority

US 9620819 W 19961230

US 57969495 A 19951228

Abstract (en)

[origin: US5658465A] The present invention relates to a method for inhibiting the formation and deposition of silica and silicate compounds in water systems by the use an effective amount of a polymer or copolymer having the following structure: <IMAGE> (I) or <IMAGE> (II) wherein A is the initiator radical from free radical polymerization, such as for example, alkoxy, acyloxy, hydroxyl, alkyl or sulfonate radicals from peroxide initiators, or cyanoalkyl radicals from azonitrile initiators, or n-alkythio or tetrahydrofuranyl radicals from common transfer agents, R1 and R2 are alkyl groups which contain a combined total of 2 to 4 carbon atoms or R1 and R2 together with the nitrogen atom comprise a ring containing 3 to 5 carbon atoms, R3 is either H or a C1 through C4 alkyl, X is selected from the group consisting of hydrogen, an n-alkyl or aralkyl chain containing up to 30 carbon atoms, and an isoalkyl chain containing 3 to 30 carbon atoms, Y an oxazolinium salt, a 1,3- oxazolinium salt, or a neutral end group derived from simple nucleophiles, m is 2 or 3, and n is an integer between 10 and 1000, which polymers may be used alone or in concert with other water treating agents, e.g. phosphoric acids and their salts, phosphonic acids and their salts, metal chelating agents, corrosion inhibitors, oxygen scavengers, homo- and copolymers of acrylic acid, homo- and copolymers of maleic acid or anhydride, and acrylic acid/maleic acid based copolymers.